Breakable connection in link arm of a door operator



April 23, 1957 V G. LA v. RUNKLE BREAKABLE CONNECTION IN LINK ARM OF A DOOR OPERATOR Filed March 24, 1955 3 Sheets-Sheet 1 IN! 'EN TOR. George [0 Var/7e Run A/e E m E E m MG =3 2 3 N 2 0/ 0 DH c mow Ran mom Lo OCP 43 37 RELEASE Conn-a g 5% A TTORNE Y5 April 23, 1957 G. LA v. RUNKLE BREAKABLE CONNECTION IN LINK ARM OF A DOOR OPERATOR Filed Mar0h24, 1955 3 Sheets-Sheet 2 George AaVe/We Punk/e WQ'M ATTOR/VE Y5 April 23, 1957 G. LA v. RUNKLE 2,789,813

BREAKABLE CONNECTION IN LINK ARM OF A DOOR OPERATOR Filed March 24, 1955 s Sheets-Sheet s L CO2 OUTLET NE 43- 37 3.5

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I N V EN TOR. George [0 M m: Al/flk/e BYQ r ATTORNEYS United States Patent BREAKABLE .CQNNEGTIDN IN LINK ARM OF A DOOR Q PERA R George La Verne Runkle, Lima, Ohio, assignor to Superior Coach Corporation, Lima, Ohio, a corporation of Ohio Appl ca ion Ma ch 2 195 Serial No 414 6 Claims. ((11. 268-62) Th investi r a e to saf t v es o s an asse an pa ieu rly o a fro t exi s f y door for tabo basses It is ei s mar in s c ba s for he ro t doors. which are usually'in pairs and serve as both entrance and exi d or to p ate i a tepel and o e f m one of the pai to o n orwa d y an ou a dly a o the Qther d or to open earwardl and n ar y t t e e This arrangem nt is bje tiona l as th blocking of he rea oor again t p ni whi h y e ca s d by or ard crowd ng o the Pa sen e s in an rg to leave the u by a Passen er t ding in the w l. or y s arti l or in tan e. a s hoolbook. pe i ul a iental y dropped thefw l m Pr v n it op ni This condition isa bad hazard when an accident occurs an h end ncy s f as en to. e w orwar t he exi and'thus h ek he front doors. a n t p n n s The object of the. present invention is to obviate this hazard b he Pr is f mpl a e ent ea i connection with the door operating mechanism, which means is manually operable in an easy manner either by the bus operator or by a passenger to break or disconnectsuchrnechanism whereby the rear door of a pair ist'ree to swing outward, and this may occur even though the front door may be held against opening by reason of an accident or otherwise.

Further objects and advantages of the invention will be apparent from the following detailed description, and rom t e ompan g rawin usu t s i e ment thereof, and in which:

He 1 i a f agmen ar ner e e i o the f nt nte io parties o a bus show n e front e tra d or he s e -well and th eer n t t p rt n do ines and ith t e doors Part y ope d o wa d. as u d mer en y;

i s a fra men a y p n vie o he fr n d o o a se its moun in end con r l. h t d or in c sed position;

Fig. 3 is an enlarged fragmentary view looking upward at the StBPv-Wfill from the bottom, as on the line 33 in Fig. l, and showing the doors and connecting linkage therefor, with the linkage broken and both doors opened outwardly to a slight extent;

Fig. 4 is a similar view,- with the operating linkage unbroken and in the normal position it assumes when the doors are both closed;

Fig. 5 is a side view partially in section, of the trigger operated release for a CO bottle in the gas operating line, and

Fig. 6 is an enlarged side view of the gas operated linkage breaking means, with a part in section.

Referring to the drawings, 1 designates a portion of the front interior end portion of a bus body having the cus tomary step-well 2 at the front entrance with the front and rear doors 3 and 4, respectively, of a pair hinged in and adapted to close the entrance. The front door 3 is hinged at its front edge to open outwardly and forice 2 wardly while the rear door 4 is hinged at its rear edge to' normally open inwardly and rearwardly in the well 2. In the present instance, for the purpose of the invention, the hinge of the rear door 4 is of the twoaway type to permit the door to swing in both directions from closed position.

In Figs. 3 and 4, the hinge shafts of the front and rear doors are extended below the bottom of the step-well, as shown, respectively, at 5 and 6. The shafts 5 and 6 are provided below the step-well 2 with crank-arms 7 and 8, respectively, and these are customarily connected by a link whereby as the front door 3 swings outward and forward, the rear door 4 is caused to swing inward and rearward.

For the purpose of the invention, the connecting link for the two crank-arms 7 and 8 is of the toggle link type and comprises the two sections 9 and 10 pivotally connected together at 11. The breaking movement of the toggle is limited in outward direction relative to the door positions by an arm 12 fixed to the side of and projecting lengthwise from the pivoted inner end of the link section 9 but in slightly inwardly angled relation to its axis. This permits the link pivot 11 to move outward toward the closed door position a distance sufficient to throw it off center relative to the axis of the link section 9, as shown in Fig. 4, before the arm 12 engages the adjacent side of the link section 10 and limits such movement. A door moving force may thus be imparted through the linkage from one crank-arm to the other. The link sections are yieldingly held in this operative off-center position by a pair of opposed spring fingers 13 which project laterally from the arms 12 and straddle the link section 10 in spring engagement therewith. The

application of force to the link section 9 adjacent to its inner end away from the closed door position throws the pivot 11 outward beyond the axial line of the link sec? tion 9 and effects a release of the spring fingers 13 from the link section 10, as shown in Fig. 3.

Secured to the under side of the step-well bottom 2a, at the inner side of the toggle link relative to the doors, is a block 14 having a cylindrical chamber 15 therein in which a plunger 16 operates. A plunger stem 17 projects outward from the chamber at a side of the block adjacent to the inner end portion of the link section 9 and when moved outward acts against a registering lug 18 on said section to release the spring fingers from the section 10 and effect a breaking of the rigid operating connection between the two link sections. The chamber 15 at the inner side of the plunger 16 is connected by a tube 1 9 to a suitable fluid pressure source, as hereinafter described.

The customary operating means for the front door 3 comprises a hand control lever 25 pivoted to a bracket 26. for horizontal swinging movements in advance of the operators seat 27. This lever is connected by a link 28 to the inner sideof the front door 3 between its front and rear edges whereby a swinging of the arm to the righteffects an opening of the door, and a reverse movement returns the door to closed position and places the link connection 29, in inward off-center locking position with respect to the lever pivot 30 (Fig. 2). it is thus apparent that the lever 25 must be swung outward a short distance from its locked position before it is free for door opening movement. As previously described, opening and closing movements of the front door 3 impart corresponding movements in reverse directions to the rear door 4.

The lever 25 is automatically released from its oilcenter locking position by a fiuid pressure operated plunger 31 mounted in a cylinder block 32 adjacent to the bracket 26 the same as described with respect to the linkage release plunger 17. Fluid pressure is directed to the cylinder block 32 through a tube 33.

The tubes 19 and 3?: connect with a tube 34 which leads from a suitable source of fluid pressure, which, in the present instance, is a CO gas bottle 35. This bottle, in the present instance, has its release end removably threaded into a socket 36 provided in a bracket 37 located above the windshield of the bus. The release end of the bottle has a perforable cap 38 (Fig. that is punctured by the inward movement of a pin 39 operating in a gas relief passage 44 in the bracket and which passage connects through an outlet 41 with the tube 34. The pin 39 is normally held retracted by a spring 42 and its outer end is engaged by a trigger lever 43 that is fulcrumed to the bracket 37 and has camming engagement with the pin whereby an inward puncturing movement is imparted to the pin when the trigger is moved by a pull on the release cord 44. This cord is located in convenient position for pulling either by the operator or by a passenger in the front of the bus. It is apparent that a release of the bottled gas actuates the plungers 17 and 31 to respectively throw the linkage pivot 11 and operating lever pivot 29 from off-center locked positions to release both front doors 3 and 4 for free outward opening movements.

This form of control for the customary operating means and connections for the front entrance and exit doors of busses permits an easy and quick release of the doors for free outward opening movements when occasion therefor arises, thus providing a safety feature that is particularly valuable for use in connection with school busses.

I wish it understood that my invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modifications and changes without departing from the spirit of the claims.

I claim:

1. In a bus having an exit opening, a pair of doors hinged at their outer vertical edges to open and close said opening, a crank-arm projecting from the hinged edge of each door, and operating means interiorly of the bus attached to one of said doors to open and close it, the improvement comprising a toggle link connection between said crank-arms operable, when unbroken, in cooperation with said cranl -arms to cause one door to open inwardly when the other is opening outwardly, an arm projecting rigidly from the inner end of one link to said connection across the joint thereof and in lapping relation to the inner end of the other link and cooperating therewith to yieldingly hold the connection in operating relation to the crank-arms, and fluid pressure operated means controlled from within the bus and operable against said connection adjacent to the jointed ends of the toggle links to effect a breaking of said connection to render it inoperative to cause joint movement of the doors.

2. In a bus having an exit opening with an associated step-well, a pair of doors hinged at their outer vertical edges to open and close said opening with one door opening into the well and the other door opening outwardly therefrom, and a connection between said doors causing them to open and close in unison, the improvement which comprises the provision of a break joint in said connection, means in connection with said joint for yieldingly holding the jointed parts in door operating relation, and fluid pressure actuated means controlled from within the bus and operable to break said joint to render said first connection inoperative and permit the inwardly opening door to open outwardly.

3. A combination as called for in claim 2, wherein said last means includes a bottle of CO gas, a connection between said bottle and pressure actuated means and means operable by either the bus operator or passengers to puncture the bottle and release the gas.

4. In a bus having an exit opening, a pair of doors hinged at their outer vertical edges to close said opening, means having an off-center locking position connected to one of said doors and operable by the bus operator to release said locking position and open its door outwardly, and a connection between said doors operable by an opening of said operator controlled door to open the other door inwardly, the improvement which consists in the provision in said connection between said doors of a breakable joint means which has a predetermined resistance to breaking, and fluid pressure operated means controlled from within the bus and operable to act on said door connection to break its said joint means whereby the inwardly opening door is free to swing outwardly.

5. In a bus having an exit opening, a pair of doors hinged at their outer vertical edges to open and close said opening, a crank-arm projecting from the hinged edge of each door, an operating means interiorly of the bus attached to one of said bars to open and close it, the improvement comprising a breakable connection between said crank-arms operable, when unbroken, in co-' operation with said crank-arms to cause one door to open inwardly when the other is opening outwardly, means controlled from within the bus and operable to break said connection to permit the inwardly opening door to open outwardly, said breakable connection including a toggle link, and means in association with said toggle link for yieldingly holding it in operating unbroken position.

6. In a bus having an exit opening, a pair of doors hinged at their outer vertical edges to open and close said opening, a crank-arm projecting from the hinged edge of each door, an operating means interiorly of p the bus attached to one of said bars to open and close it, the improvement comprising a breakable connection between said crank-arms operable, when unbroken, in

cooperation with said crank-arms to cause one door to cluding a toggle link, and means in association with said toggle link for yieldingly holding it in operating unbroken position, said last means having a plunger operable against said breakable connection to effect a breaking thereof when the connection is to be rendered inoperative.

References Cited in the file of this patent UNITED STATES PATENTS Brockway Jan. 21, 1941 2,229,273 Potter et al. Mar. 17 942 

